Air Compressor Pipes Materials

Air Compressor Pipes Materials

Air Compressor Pipes Materials

Air compressor pipes come in many materials, but the most common ones found in a garage or shop are copper, black iron pipe, or a aluminum or polyethylene system like RapidAir. Each of these have their pro’s and con’s. I will review each of these below.

I do not recommend PVC pipe as it can shatter sending shrapnel through the air.

Copper Pipe

Copper piping is one of the best choices for affordable compressed air piping. It is my first choice and what I would recommend so it will be discussed more than the other options. It is lightweight, corrosion resistant, somewhat easy to assemble, and has a very smooth bore which reduces frictional pressure losses with air. One of the most beneficial things about copper is that is an excellent material to cool the compressed air flowing through the pipes. This allows the moisture in the air to condense into a liquid allowing you to catch it with a water filter. It is most commonly sold in 10 foot lengths from $14 to $20 depending on which type you get. While the pipes themselves are more expensive than black iron pipe, the fittings are cheaper than iron fittings. One of the downsides to copper pipe is that it must be soldered together. Luckily, all of the tools required to do solder copper pipes and fittings are very cheap and there is not much of a learning curve. The very first copper fitting I ever soldered in my life has never leaked and is still fine to this day.

Hard copper pipe comes in three wall thicknesses. Type M is the thinnest, then Type L, and Type K is the thickest. Type M or L pipe will last many years in home garages or shops. I have had no issues with the thinnest Type M copper pipe in my home garage but in a shop, where the copper pipe has more of a chance of being bashed up against by something, Type L copper pipe would be more suitable. If you want to play it very safe and don ‘t mind spending the extra money, there is Type K copper pipe.

Air Compressor Pipes Materials

How to Solder Copper Pipe and Fittings:

1. First the copper pipes must be cut to the desired length using an appropriately sized tubing cutter.

2. The cutting will leave an edge on the inside diameter of the pipes that must be removed before soldering, this can be done with a de-burring tool.

3. Once your cut is made, you must remove any oxidation from the pipes where it inserts into the fitting. This should be done by using emery cloth on the outside of the copper pipe and the fitting until the copper is shiny. The first inch or so of the inside of the pipes and fitting also need to be cleaned until shiny. This can be done with an appropriately sized wire brush that fits your pipe.

4. Now that your pipes are cut and cleaned, you will apply a very light coat of soldering flux on the outside of the copper pipes and on the inside of the fitting. This only needs to be applied where the two meet together. Do this for each pipe and you can then press them together. Make sure the pipe is fully seated into the fitting before continuing. Wipe off any excess flux. I highly recommend the tinning flux linked above as it is very easy to get a leak free solder joint.

5. You must prepare the entire fitting before soldering. If you are using an elbow fitting, you must have two copper pipes prepped, fluxed, and inserted into each end of the elbow before soldering. If using a 3-way tee fitting, then three copper pipes prepped, fluxed, and inserted into each hole before soldering and so on. You do not have to build your entire piping system all at once before soldering, but the fitting must be completely assembled.

6. To do the actual soldering, you will need a propane torch head and propane cylinder. While the heads are cheaper online, the propane tanks are only about $4 at your local hardware store. You will use your propane torch to heat up the middle of the copper fitting, do not aim it at the solder joint. Unroll a length of solder and hold it on the joint on the opposite side of the flame. Once the joint is hot enough, the solder and start to flow into the joint. Start to move the solder around the joint until the entire joint is soldered. You do not want to add too much as it can glob up inside the joint. Once you finish soldering one side of the finish, move your copper to the next side of the same fitting and repeat. Once all sides of the one fitting are soldered, you can remove the torch from the joint. If the next joint you are about to solder is close to the previous joint, you can wrap a wet rag around the completed joint to keep it from re-melting. If you have to solder close to a wall you can hang up a soldering pad on the wall to prevent burning down your garage.

7. Once your solder joint is completed, wipe the joint with a damp rag to remove any excess flux. The flux is acidic and if left on the pipe, can cause corrosion. Also inspect the solder joint to ensure that is filled in completely.